SHIZUGAWA, Japan — Growing up in this small fishing town on Japan's northeastern coast, 16-year-old Minami Sato never took the annual tsunami drills seriously.

She thought the town's thick, two-story-high harbor walls would protect against any big wave. Besides, her home was perched on a hilltop more than a mile (about two kilometers) from the water's edge. It was also just below a designated "tsunami refuge" — an elevated patch of grass that looked safely down across the town's highest four-story buildings.

But the colossal wave that slammed into Shizugawa last week "was beyond imagination," the high-school student said. "There was nothing we could do, but run."

The devastating tsunami that followed Friday's massive earthquake erased Shizugawa from the map, and raised questions about what, if anything, could have been done to prevent it. More than half the town's 17,000 people are missing and scenes of ruin dot the towns and villages along Japan's northeastern coast, devastation not seen here since the U.S. dropped atomic bombs on Hiroshima and Nagasaki during World War II.

On Wednesday, the official death toll from the tragedy was raised to 3,676 but it is expected climb above 10,000 as nearly 8,000 people are missing. Some 434,000 people were made homeless and are living in shelters.

With each passing day, more and more poignant stories of survivors and victims are emerging.

Immediately after the quake, Katsutaro Hamada, 79, fled to safety with his wife. But then he went back home to retrieve a photo album of his granddaughter, 14-year-old Saori, and grandson, 10-year-old Hikaru.

Just then the tsunami came and swept away his home. Rescuers found Hamada's body, crushed by the first floor bathroom walls. He was holding the album to his chest, Kyodo news agency reported.

"He really loved the grandchildren. But it is stupid," said his son, Hironobu Hamada. "He loved the grandchildren so dearly. He has no pictures of me!"

Shizugawa, 30 miles (50 kilometers) from Hamada's home in Iwate province's Ofunato city, had been preparing for just such a disaster since at least 1960, when the largest earthquake on record — a magnitude 9.5 — hit Chile and triggered a tsunami that swept the entire Pacific Ocean and hit Japan.

A Miyagi prefecture official said the harbor walls, which began to be constructed soon after the tsunami, were completed in 1963.

Every year on the anniversary of that destruction — May 22 — residents of Shizugawa practiced tsunami drills — running to designated refuges on higher ground scattered through town as sirens howled and making arrangements for emergency food and shelter.

The drills were voluntary, but most people took part, said 50-year-old housewife, Katsuko Takahashi, who was sitting in the darkness outside a school turned shelter in Shizugawa, shivering as snow fell.

"I can't say we prepared enough, because half the population is still missing," she said. "But you cannot prepare for a tsunami this big."

When Sato first saw the colossal brown wave rushing toward Shizugawa on Friday afternoon, it looked small enough for the 20-feet-high (6-meter-high) walls along the harbor — hundreds of feet (meters) of thick concrete slabs — to stop it.

But as the tsunami slammed into the harbor edge, it was clear the walls, stretched over a half-mile (a kilometer), would be useless. Sato — watching from her hilltop home — saw the surging water easily engulf not only the walls, but crash over the top of four-story-high buildings in the distance.

Sato grabbed her 79-year-old grandmother and started running up a pathway behind her home to the tsunami refuge.

But there, she saw several dozen people who had gathered already on the move.

The wave fast approaching, Sato ran up the steps into a Shinto shrine, past a cemetery and kept going, finally coming to a halt out of breath beside a cell phone tower.

The surging sea swept over the refuge below them, picking up 16 cars that had been parked neatly in a row and cramming them chaotically together into a corner of the parking lot.

Below, the ocean had swallowed all of Shizugawa, rising above a four-story mini-mall and the town's hospital, two of the few buildings still standing — but totally gutted — when the wave receded.

"I thought I was going to die," Sato said Tuesday afternoon, as she gathered up two sweaters, two books and a pillow from her ruined house, whose missing front wall looked out over the town, where a line of army-green Japanese Self Defense Force jeeps rode through the destruction.

The harbor wall is now half missing. On one road that still exists in Shizugawa, evacuation routes can still be seen painted into the tarmac.

One shows a blue wave curled around a running human figure. A green arrow indicates a refuge is just a few hundred yards (meters) away — the same one now covered with debris beside Sato's house.

Just around the corner, the road is gone, surrounded by an apocalyptic wasteland of knotted rubble that used to be Shizugawa.